Outer package for packaged groups of rolls of products

ABSTRACT

An outer package for groups of rolls of products, each group consisting of a plurality of rolls of products wrapped and closed in a piece of plastic film to form a pack; the outer package comprises a sheet of film for packaging one or more packs, which can be wrapped around said packs by forming a tubular wrapper with the sheet by gradually folding it in such a way as to obtain a tubular shape with a pair of longitudinal edges and two external edges, front and rear of the outer package, which can be closed on the packs with relative seals; the sheet of film consists of a material with a heat conducting value, and at least on the edges of its surface which can be placed opposite the packs, a zone with heat conducting properties lower than the afore-mentioned value and designed to allow, respectively, a seal for the pair of longitudinal edges overlapping one another and close to the packs and relative folding of the front and rear edges so that each forms two folded wings, which can be placed overlapping one another, and can be sealed together at end zones, to prevent the film used for the packs from being affected in the seal zones.

BACKGROUND OF THE INVENTION

The present invention relates to an outer package for packaged groups of rolls of products (and the method for its production).

The present invention is used in particular in the field of forming outer packages for groups of rolls of products, placed on top of one another, such as strips of kitchen or toilet paper.

In said technical field, the rolls of product are normally packaged in groups of products in a variety of formats, that is to say, containing a predetermined number of rolls which, for improved manageability and transport, are usually packaged in layers on top of one another (for example packs of 3×3, 4×2, 8×2, etc.).

To obtain these packs, there are known machines with devices known to experts in the trade as forming units, for stacking layers of rolls fed individually and one after another from a roll production unit located upstream of the forming unit.

The rolls, stacked in layers by the forming units, are then transferred to a packaging unit which packages them in a material consisting of a web (usually a plastic film) and closes this around the group, using sealing units, both longitudinally and at the front and rear of the group of products.

These groups of products packaged with film are then carried to a handling unit designed to allow the formation of loose batches of groups of products which can be directly positioned on pallets, or batches of groups of products sent to a bagging or overwrapping unit in which two or more groups of products are wrapped in another sheet of heat-sealable film to form a bag containing groups of products having a greater number of products (depending on the manufacturer's requirements).

As regards the afore-mentioned overwrapping of two or more groups of products, the outer package A of the packs P of rolls of products is currently produced as is clearly shown in FIG. 1.

Said outer package A is produced by the bagging unit which forms the wrapper starting with a flat strip of packaging material film which, by means of special folding elements, is gradually folded over itself to create a tubular shape, supported from inside the wrapper being formed by suitable supporting elements and having longitudinal edges L1 and L2 which are drawn near one another.

Sealing means positioned in front of the wrapper and angled transversally to the tubular shape allow the wrapper to be sealed transversally to form, one after another, a closed front end T1 and rear end T2. Additional sealing means, angled longitudinally to the wrapper A and opposite the longitudinal edges L1 and L2, close the tubular wrapper A longitudinally with a seal S.

The longitudinal sealing means normally consist of a sealing bar, using an air jet, positioned above or at the edges L1 and L2 of the film, whilst below these edges L1 and L2 a plate is inserted to separate the sealing zone from the individual packs P of groups of products (through the rear part of the wrapper, not yet closed).

Such bagging units produce a low number of bags per unit of time compared with the packaging units which seal the groups of products: this is mainly because the sealing steps must be carried out with the edges of the overwrapping film separated or distanced from the packaged groups, to prevent contact between the films which could result in the overwrapping film and the film used for the packs being joined, or deterioration of the film used for the pack.

SUMMARY OF THE INVENTION

Therefore, in this context, the Applicant has invented and produced an outer package for packaged groups of rolls of products with characteristics which allow a faster step of closing by sealing and without risks of deterioration in the packs of groups of rolls of product inside it.

The technical purpose indicated and the aims specified are substantially achieved by an outer package for packaged groups or packs of rolls of products comprising the technical features described in one or more of the claims herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the present invention are more apparent in the detailed description below, with reference to a preferred, non-limiting, embodiment of a unit for forming packs of products at a packaging machine and a relative method for forming packs of products, illustrated in the accompanying drawings, in which:

FIG. 1 is a perspective view of a known type of outer package for packaged groups or packs of rolls of products;

FIG. 2 is a perspective view of an outer package for packaged groups or packs of rolls of products in accordance with the present invention;

FIG. 3 is a schematic front view of the outer package from FIG. 2;

FIG. 4 illustrates an enlarged detail from FIG. 3;

FIGS. 5, 6 and 7 are relative schematic perspective views of a sequence of steps of folding and closing the outer package in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the accompanying drawings, and in particular with reference to FIG. 2, the outer package, labeled 3 as a whole, is used to wrap groups of rolls of products which, in the preferred embodiment illustrated in the accompanying drawings, are preferably toilet or kitchen paper.

These groups of products 1 each consist of a plurality of rolls of products, grouped together to constitute a format, and wrapped and closed in a piece of plastic film 2 to form a pack C.

The outer package 3 comprises a sheet 4 of film for packaging one or more of the packs C. The sheet can be fed individually or continuously (for example from a reel, not illustrated) then cut to the appropriate size.

As also illustrated in FIGS. 5 to 7, the sheet 4 can be wrapped around the packs C of products by forming a tubular wrapper with the sheet 4 by gradually folding it in such a way as to obtain a tubular shape with a pair of longitudinal edges 5 and 6 and two external edges 7 and 8, front T1 and rear T2 of the outer package 3, which can be closed on the packs C by means of seals S1, S2 and S3.

This sheet 4 of film consists of a material with a heat conducting value A to allow the seals S1, S2, S3 to be made.

The sheet 4 also has, at least on the edges 9 of its surface 4 a which can be placed opposite the packs C, a zone with heat conducting properties B lower than the afore-mentioned value A and designed to allow, respectively:

a seal S1 for the pair of longitudinal edges 5 and 6 overlapping one another and close to the packs C and

relative folding of the front and rear edges 7 and 8 to form two folded wings 7 a and 8 a for each edge 7 and 8, which can be placed overlapping one another, and can be sealed together at end zones S2 and S3.

Therefore, the presence of the edges 9 with lower heat conductivity allows the seals S1, S2 and S3 to be made without affecting the film 2 used for the packs C in the seal zones S1, S2 and S3.

For example, the edges 9 of the sheet 4 of film may have zones consisting of a substance with the aforementioned heat conducting values B lower than the heat conducting values A of the rest of the sheet 4.

As illustrated in FIGS. 3 and 4, the sheet 4 of film may consist of two layers 4 a and 4 b, forming the external surface 4 a of the outer package 4 and, respectively, the internal surface 4 b which can be placed opposite the packs C.

The internal layer 4 b has the heat conducting values B designed to allow sealing of the edges 5 and 6 and of the end zones S2 and S3 of the wings 7 a and 8 a overlapping and close to the packs C.

Again in this case, obviously, the internal surface 4 b of the sheet 4 of film consists of a substance with the heat conducting values B lower than the heat conducting values A of the upper surface 4 a of the sheet 4 of film.

Alternatively, the sheet 4 of film may consist of two separate films 4 a and 4 b, joined together to form the afore-mentioned two layers, where the first film forms the internal surface 4 a with the heat conducting values B lower than the heat conducting values A of the other film 4 a forming the external surface of the sheet 4 of film.

Obviously, as already indicated, the sheet 4 may be fed individually, or continuously from a reel, and may be folded and sealed like the packs it is wrapped around thanks to the presence of the edges 9 or the internal layer or film 4 b which prevents the heat generated from the outside for the sealing from causing a deterioration of or damaging the film 2 used for the packs C.

This possibility therefore allows the outer package folding and sealing steps to be performed more safely and with much faster production speeds, partly because it is possible to use apparatuses very similar to those used for forming the packs C.

The invention described has evident industrial applications and may be modified and adapted without thereby departing from the scope of the inventive concept. Moreover, all details of the invention may be substituted by technically equivalent elements. 

1) An outer package for groups of rolls of products, each group comprising a plurality of rolls of products grouped together to constitute a format, and wrapped and closed in a piece of plastic film to form a pack; the outer package comprising a sheet of film for packaging one or more packs, which can be wrapped around said packs of products by forming a tubular wrapper with the sheet by gradually folding it in such a way as to obtain a tubular shape with a pair of longitudinal edges and two external edges, front and rear of the outer package, which can be closed on the packs with relative seals, wherein the sheet of film comprises a material with a heat conducting value, the sheet including, at least on the edges of its surface which can be placed opposite the packs, a zone with heat conducting properties lower than said value and designed to allow, respectively, a seal for the pair of longitudinal edges overlapping one another and close to the packs and relative folding of the front and rear edges so that each forms two folded wings, which can be placed overlapping one another, and can be sealed together at end zones, preventing the film used for the packs from being affected in the seal zones. 2) The outer package according to claim 1, wherein the sheet of film comprises two layers, forming the external surface of the outer package and, respectively, the internal surface which can be placed opposite the packs; the internal layer having the heat conducting values designed to allow sealing of the edges and the end zones of the wings overlapping and close to the packs. 3) The outer package according to claim 1, wherein the edges of the sheet of film include zones comprising a substance with said heat conducting values lower than the heat conducting values of the rest of the sheet. 4) The outer package according to claim 2, wherein the internal surface of the sheet of film comprises a substance with said heat conducting values lower than the heat conducting values of the upper surface of the sheet of film. 5) The outer package according to claim 2, wherein the sheet of film comprises two separate films, joined together so that the first forms the internal surface with the heat conducting values lower than the heat conducting values of the other film forming the external surface of the sheet of film. 6) The outer package according to claim 4, wherein the sheet of film comprises two separate films, joined together so that the first forms the internal surface with the heat conducting values lower than the heat conducting values of the other film forming the external surface of the sheet of film. 